PDF malware analysis — malicious · b91943427b76a9ee

MALICIOUS

PDF

15.7 KB

MD5: 8fe2807003125f4755d52de31a9f2714 SHA-1: 2b4c757340822dff34834bba0040a00e96ef6bde SHA-256: b91943427b76a9eedb7772559ab336c05ff538d1a6e2391e9c69b60339c4db65

166 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 PowerShell T1204.002 Malicious File T1566.001 Spearphishing Attachment T1071.001 Web Protocols

The PDF file contains embedded JavaScript that utilizes `eval()` and `String.fromCharCode()` functions, indicating an attempt to obfuscate malicious code. Heuristics suggest this JavaScript acts as a stager, likely downloading and executing a second-stage payload. The ClamAV detection `Pdf.Exploit.Agent-36086` further confirms its malicious nature, pointing towards a known exploit targeting PDF documents.

Heuristics 7

ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
eval() call high PDF_EVAL

eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL

PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
JavaScript action low PDF_JAVASCRIPT

PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
Embedded JS stream low PDF_JS

PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
String.fromCharCode low PDF_FROMCHARCODE

String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`javascript_obj0006_000.js` `d6e324e7353b61ef1e174e5a8b53a3ad5d9062c0f965b3efffbcdeeb2b406543`	pdf-javascript-stream	PDF /JS object 6 at offset 0x143	424828 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).

Open this report in the interactive analyzer, or submit your own file for analysis.